Storage device and control method

ABSTRACT

According to one embodiment, a storage device includes a control apparatus and a stocker. The control apparatus writes data to or reads data from a storage medium that includes a plurality of non-volatile memory chips. The stocker stores a plurality of the storage media that are detached from the control apparatus. The control apparatus includes a first temperature control system. The first temperature control system raises temperature of the storage medium to a first temperature or higher. The stocker includes a second temperature control system. The second temperature control system cools the storage medium to a second temperature or lower. The second temperature is lower than the first temperature.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation Application of PCT Application No.PCT/JP2019/044931, filed Nov. 15, 2019, the entire contents of which areincorporated herein by reference.

FIELD

Embodiments described herein relate generally to a storage device and acontrol method.

BACKGROUND

Recently, various storage devices such as a solid state drive (SSD) anda hard disk drive (HDD) have been used. For example, a NAND flash memorymounted on an SSD is manufactured by forming a plurality of NAND flashmemories as semiconductor chips on a semiconductor wafer and then dicingthem.

Furthermore, a probe card is used as an inspection jig that relayselectrical signals between the semiconductor wafer on which thesemiconductor chips are formed and an inspection device that inspectsthe semiconductor chips. In simplified terms, the probe card is includesa printed circuit board PCB and a probe. A prober brings a pad electrodeformed on the semiconductor wafer into contact with the probe of theprobe card, and, for example, electrically connects a device on theprinted circuit board PCB and the semiconductor wafer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an example of a configuration of a storage device of anembodiment.

FIG. 2 shows a state in which a probe of a probe card is in contact witha pad electrode formed on a wafer in the storage device of theembodiment.

FIG. 3 is a schematic block diagram of the storage device of theembodiment.

FIG. 4 is a diagram for explaining an example of a setting of atemperature control area relating to a stage in the storage device ofthe embodiment.

FIG. 5 shows an example of a configuration of a heating and coolingsystem provided in the stage of the storage device of the embodiment.

FIG. 6 shows an example of an arrangement of the heating and coolingsystem in the stage of the storage device of the embodiment.

FIG. 7 is a diagram for explaining an example of a temperature controlby the heating and cooling system provided in the stage in the storagedevice of the embodiment.

FIG. 8 is a diagram for explaining an example of a mechanism in which adevice on the probe card centrally controls the temperature of theprober in the storage device of the embodiment.

FIG. 9 shows a plurality of probes disposed on a first side of the probecard in the storage device of the embodiment.

FIG. 10 shows a plurality of controllers disposed on a second side ofthe probe card in the storage device of the embodiment.

FIG. 11 is a diagram for explaining an example of an operation of thedevice implemented on the prober in the storage device of theembodiment.

FIG. 12 shows a first example of a cooling system provided in a stockerin the storage device of the embodiment.

FIG. 13 shows a second example of the cooling system provided in thestocker in the storage device of the embodiment.

FIG. 14 is a flowchart showing an example of a flow of temperaturecontrol during wafer replacement executed in the storage device of theembodiment.

DETAILED DESCRIPTION

Embodiments will be described hereinafter with reference to theaccompanying drawings.

In general, according to one embodiment, a storage device includes acontrol apparatus and a stocker. The control apparatus writes data to orreads data from a storage medium that includes a plurality ofnon-volatile memory chips. The stocker stores a plurality of the storagemedia that are detached from the control apparatus. The controlapparatus includes a first temperature control system. The firsttemperature control system raises temperature of the storage medium to afirst temperature or higher. The stocker includes a second temperaturecontrol system. The second temperature control system cools the storagemedium to a second temperature or lower. The second temperature is lowerthan the first temperature.

FIG. 1 shows an example of a configuration of a storage device 1 of thepresent embodiment.

In the present embodiment, it is assumed that a probe card, which is aninspection jig, is diverted to build a large-capacity storage device 1using semiconductor wafers without dicing the wafers. Furthermore, it isassumed that the semiconductor wafers that are electrically connectableto probes can be replaced and that a larger-capacity storage device 1 isbuilt by using multiple semiconductor wafers.

In constructing such a storage device 1, it is preferable that thetemperature of the semiconductor wafers in the prober be kept at hightemperature, above room temperature, and the temperature be kept at auniform temperature within the semiconductor wafer, while thetemperature of the semiconductor wafers stored outside the prober bekept at low temperature, below the room temperature.

The storage device 1 includes a reader and writer (prober) 100, astorage conveyance system 200, and a stocker 300. In FIG. 1, an examplewhere two probers 100 are provided is shown. However, it is not limitedthereto, and the number of probers 100 may be changed in various ways.In addition, the storage device 1 includes an air conditioning controlsystem 500 for replacing the atmosphere in the prober 100, the storageconveyance system 200, and the stocker 300 with dry air, noble gas,inert gas, or the like that does not contain water.

The storage device 1 is equipped with a semiconductor wafer (wafer 400),as a storage, on which a plurality of NAND flash memory chips (NANDchips) are formed. The storage device 1 is equipped with a plurality ofwafers 400, and selects and uses a predetermined number of wafers 400(two wafers 400 in the case of the example shown in FIG. 1) asappropriate from among the plurality of wafers 400. Specifically, thestorage device 1 can replace the wafer 400 in the prober 100 with thewafer 400 in the stocker 300.

The prober 100 includes a probe card 110, a stage 120, and a drive unit130.

The probe card 110 is a unit that electrically connects to the wafer 400on the stage 120. As mentioned above, the probe card 110, in simplifiedterms, includes a printed circuit board PCB and a probe. In the storagedevice 1 of the present embodiment, a controller that controls writingof data to the NAND chip and reading of data from the NAND chip formedon the wafer 400, or the like, is mounted on the printed circuit boardPCB of the probe card 110 as a device 111. In addition, in the storagedevice 1 of the present embodiment, a temperature control system (aheating and cooling system 112, a cooling system 113, and a heatinsulating material 114) is provided in the probe card 110. Thetemperature control system provided in the probe card 110 will bedescribed later.

The stage 120 is a unit that holds the wafer 400. In the storage device1 of the present embodiment, a temperature control system (a heating andcooling system 121) is also provided in the stage 120. The temperaturecontrol system provided in the stage 120 will also be described later.

The drive unit 130 is a unit that moves the stage 120 to bring the probeof the probe card 110 into contact with pad electrodes formed on thewafer 400. Here, it is assumed that the drive unit 130 moves the stage120, but it may also move the probe card 110. The drive unit 130 mayalso move both the probe card 110 and the stage 120. The drive unit 130may also move the stage 120 so as to pull the probe that is in contactwith the pad electrode away from the pad electrode.

FIG. 2 shows a state in which a probe 115 of the probe card 110 is incontact with a pad electrode 410 formed on the wafer 400 by the driveunit 130.

When the probe 115 comes into contact with the pad electrode 410, acontroller mounted on the printed circuit board PCB of the probe card 11as one of the devices 111 is electrically connected to the NAND chipthat is formed on the wafer 400. This allows the controller to controlwriting of data to the NAND chip, reading of data from the NAND chip,and erasing of data in the NAND chip.

Returning to FIG. 1, the description of a configuration example of thestorage device 1 will continue.

The storage conveyance system 200 includes a storage conveyer 210.

The storage conveyer 210 conveys the wafers 400, which are the storagein the storage device 1 of the present embodiment, from the stocker 300to the prober 100, or from the prober 100 to the stocker 300. Note thatthe configuration described below is an example, and the means forconveying the wafers 400 is not limited thereto. The storage conveyer210 can move in the vertical and horizontal directions. The storageconveyer 210 includes a support 211 that can be rotated with thevertical direction as an axis, and a tray 212 that, for example, has anelongated plate-like shape and is supported by the support 211 at oneend so that the other end of the longitudinal direction protrudes in ahorizontal direction. In the case of replacing the wafers 400 in thestocker 300, the storage conveyer 210 first performs operations forconveying wafers 400 from the prober 100 to the stocker 300.Specifically, the operations are performed by a procedure such as (1)moving the tray 212 in the vertical direction so that the height becomesa suitable height for taking out the wafer 400 in the prober 100, (2)rotating the tray 212 to face the prober 100 side, (3) moving the tray212 in the horizontal direction toward the prober 100 side to hold thewafer 400 in the prober 100, (4) moving the tray 212 in the horizontaldirection toward the opposite side of the prober 100 to detach the wafer400 from the prober 100, (5) rotating the tray 212 to face the stocker300 aide, (6) moving the tray 212 in the vertical direction so that theheight becomes a suitable height for storing the wafer 400 in thestocker 300, (7) moving the tray 212 in the horizontal direction towardthe stocker 300 side to store the wafer 400 in the stocker 300, and (8)moving the tray 212 in the horizontal direction toward the opposite sideof the stocker 300 to remove the tray 212 from the stocker 300. Thisprocedure is only an example and can be changed in various ways, such asreversing the order of (1) and (2), reversing the order of (6) and (7),etc.

Secondly, the storage conveyer 210 then performs an operation forconveying the wafer 400 from the stocker 300 to the prober 100. Sincethis procedure is similar to the operation for conveying the wafer 400from the prober 100 to the stocker 300, descriptions thereof will beomitted.

The stocker 300 stores a plurality of wafers 400 which are detached fromthe prober 100. In the storage device 1 of the present embodiment, atemperature control system (cooling system 310) is also provided in thestocker 300. The temperature control system provided in the stocker 300will be described later.

The air conditioning control system 500 is structured to separate thespace in the prober 100 and the like from the outside air, and toreplace the inside of the space with dry air, noble gas, inert gas, orthe like by flowing them that are absorbed from outside into the spacedepressurized with an exhaust fan. The reason why the air conditioningcontrol system 500 replaces the atmosphere in the prober 100, thestorage conveyance system 200, and the stocker 300 with dry air, noblegas, inert gas, or the like that does not contain water will beexplained later.

FIG. 3 is a block diagram schematically showing the storage device 1that includes the prober 100, the storage conveyance system 200, and thestocker 300 described with reference to FIG. 1.

As described above, in the storage device 1 of the present embodiment, acontroller 111-1 that controls writing of data to the NAND chip andreading of data from the NAND chips formed on the wafer 400 is mountedon the printed circuit board PCB of the probe card 110 as one of thedevices 111. A plurality of controllers 111-1 may be mounted. That is,all NAND chips on the wafer 400 can be controlled by a single controller111-1 or by multiple controllers 111-1. FIG. 3 shows an example inwhich, in the same manner as the controller 111-1, a buffer memory 111-2for temporarily storing write and read data is mounted on the printedcircuit board PCB of the probe card 110 as one of the devices 111. Thebuffer memory 111-2 may be integrated into the controller 111-1.

The controller 111-1 is electrically connected to the NAND chip of thewafer 400 when the probe 115 of the probe card 110 comes in contact withthe pad electrode 410 of the wafer 400 on the stage 120. The controller111-1 is capable of controlling writing of data to the NAND chip andreading of data from the NAND chip in response to a request from a host2. In addition, the wafer 400 in the prober 100 can be replaced with thewafer 400 stored in the stocker 300 by the storage conveyance system200.

The storage device 1 includes a control unit 10. The control unit 10includes, for example, an air conditioning control unit 11, atemperature control unit 12, a drive control unit 13, and an interfacecontrol unit 14, and controls the entire operation of the storage device1. Each control unit of the control unit 10 is realized, for example, bya processor executing firmware. The air conditioning control unit 11controls the air conditioning control system 500. The temperaturecontrol unit 12 integrally controls the temperature control system inthe probe card 110 (the heating and cooling system 112 and the coolingsystem 113), the temperature control system in the stage 120 (theheating and cooling system 112), and the temperature control system inthe stocker 300 (the cooling system 310). The drive control unit 13controls the drive unit 130 and the storage conveyer 210. The interfacecontrol unit 14 controls the communication between the host 2 and theprobe card 11. The interface control unit 14 controls the airconditioning control unit 11, the temperature control unit 12, and thedrive control unit 13 based on the control results of the communication.

The writing of data to the NAND chip and the reading of data from theNAND chip of the wafer 400 are preferred to be performed at a hightemperature (for example, 75° C., but, for example, 85° C. or lower),above room temperature. More specifically, when data is written to andread from a memory cell in a NAND chip, the higher the temperature, thedeeper and more stable the level at which electrons are trapped in thecharge storage layer of the memory cell becomes, thereby reducingvariations in noise per electron. Therefore, high temperature ispreferable. On the other hand, for long-term storage of data in the NANDchip, low temperature (for example, 0° C. or lower), below the roomtemperature, is preferred. In more detail, charge retention time can belengthened by suppressing the phonon scattering of the charge stored inthe NAND chip. Therefore, low temperature is preferable when storing thewafer 400. Also, it is preferable to operate the device 111 implementedon the probe card 110 at a temperature equal to or lower than athreshold value. Thus, in the case of using the wafers 400 as storage,various temperature controls are required within the storage device 1.Therefore, the storage device 1 of the present embodiment has atemperature control system provided for each of the prober 100, thestorage conveyance system 200, and the stocker 300, so that appropriatetemperature control may be performed for the storage device 1 as awhole. This point is described in detail below.

First, the temperature control system provided in the prober 100 will bedescribed.

As mentioned above, in the prober 100, temperature control systems areinstalled in the probe card 110 and in the stage 120.

In the stage 120 that holds the wafer 400, the heating and coolingsystem 121 is provided (see FIG. 1) to make the temperature in the wafer400 electrically connected to the probe card 110 on the stage 120 asuniform as possible. The heating and cooling system 121 is a temperaturecontrol system using, for example, electric heating and cooling tubes.To control the temperature of the wafer 400 by the stage 120, thestorage device 1 sets a temperature control area for each of areassmaller than the wafer 400, for example, for each NAND chip area in thewafer 400, so that different temperature control can be performed foreach of them.

FIG. 4 is a diagram for explaining an example of a setting of thetemperature control area relating to the stage 120 in the storage device1 of the present embodiment.

FIG. 4, part (A) shows a top surface of the wafer 400 and an example ofone formation of a NAND chip 420 in the wafer 400. On the other hand,FIG. 4, part (B) shows a top surface of the stage 120 holding the wafer400, and shows an example of a setting of a temperature control area a1for the stage 120.

As shown in FIG. 4, in the storage device 1 of the present embodiment,for example, a plurality of temperature control areas a1 are set on thestage 120 so that they correspond one-to-one in position to a pluralityof NAND chips 420 formed on the wafer 400 that is disposed on the stage120. For example, the plurality of temperature control areas a1 can alsobe set so that one area corresponds to two or more NAND chips 420 inposition. The number of NAND chips to which the temperature control areaa1 corresponds does not have to be the same for all the temperaturecontrol areas a1.

FIG. 5 shows an example of a configuration of the heating and coolingsystem 121 provided in the stage 12 to control the temperature of eachtemperature control area a1 set as shown in, for example, FIG. 4.

The cooling system of the heating and cooling system 121 has a structurein which refrigerant b1 is distributed from one of two cooling tubes1211 to the other via a cooling branch tube 1212. The refrigerant b1 iswater or liquid nitrogen, etc., cooled by electronic cooling. Thecooling branch tube 1212 is disposed so that the wafer 400 on the stage120 can be cooled per the temperature control area a1 set on the stage120. The cooling by the cooling branch tube 1212 is controlled by theinflow amount of the refrigerant b1. To control the inflow amount of therefrigerant b1, an electronically controlled motor valve 1213 and a flowmeter 1214 are installed, for example, near the inlet of the coolingbranch tube 1212.

On the other hand, the heating system of the heating and cooling system121 is, for example, configured by using heater wires 1215 that aredisposed to heat the wafer 400 on the stage 120 per the temperaturecontrol area a1 set on the stage 120. The heating by the heater wires1215 can be controlled by, for example, a switch for switching whetheror not to. perform heating and a variable resistor for adjusting thecalorific value.

Note that, although details will be described later, the heating andcooling system 121 of the stage 120 configured in this manner iscontrolled by, for example, the controller 111-1 mounted on the probecard 110. In the stage 120 is provided, for example, a thermometercapable of outputting temperature data to an I²C bus. A thermometer mayalso be provided in the wafer 400.

Between the probe card 110 and the stage 120, a communication path isprovided that is capable of transferring the temperature measured by thethermometer provided in the stage 120 or in the wafer 400 to thecontroller 111-1. In cooperation with the control unit 10, thecontroller 111-1 controls the heating and cooling system 121 of thestage 120 based on the temperature measured by the thermometer providedin the stage 120 or in the wafer 400. In a case where there are multiplecontrollers 111-1, one of them may be responsible for controlling theheating and cooling system 121, or multiple controllers 111-1 may workin cooperation to control the heating and cooling system 121. Thecontrol of the temperature control systems (the heating and coolingsystem 112 and the cooling system 113) provided in the probe card 110,as described below, is also executed by the controller 111-1. In otherwords, the temperature control systems in the prober 100 are centrallycontrolled by the controller 111-1. A device for centrally controllingthe temperature control systems in the prober 100 may be providedseparately from the controller 111-1 and mounted on the probe card 110.Alternatively, a device other than the controller 111-1 may be equippedwith a function for centrally controlling the temperature controlsystems in the prober 110.

Also, FIG. 5, a lift pin 131 and an actuator 132 of the drive unit 130are shown together. The lift pin 131 is a member that is fitted into ahole provided on the stage 120 and moves the stage 120 in a verticaldirection or a horizontal direction. The actuator 132 can move the stage120 in the vertical or the horizontal direction by moving the lift pin131 in the vertical or the horizontal direction. The movement in thehorizontal direction is performed to align the positions of the padelectrode 410 of the wafer 400 and the probe 115 of the probe card 110.On the other hand, the movement in the vertical direction is performedso that the pad electrode 410 of the wafer 400 and the probe 115 of theprobe card 110 come in contact, or so that the pad electrode 410 and theprobe 115 that are in a contact state are separated.

FIG. 6 shows an example of an arrangement of the heating and coolingsystem 121 in the stage 120, which is configured as shown in, forexample, FIG. 5.

FIG. 6, part (A) shows a top surface of the wafer 400 and an example ofone formation of a NAND chip 420 in the wafer 400. On the other hand,FIG. 6, part (B) shows a top surface of the stage 120 holding the wafer400, and an example of an arrangement of the heating and cooling system121 in the stage 120.

The cooling branch tubes 1212 for cooling and the heater wires 1215 forheating provided in the heating and cooling system 121 described withreference to FIG. 5 do not necessarily have to be disposed to go throughall the temperature control areas a1, as shown in FIG. 6, part (B). Forexample, one or more cooling branch tubes 1212 in the vicinity or one ormore heater wires 1215 in the vicinity can be used to control thetemperature of the desired temperature control area a1.

FIG. 7 is a diagram for explaining an example of temperature control bythe heating and cooling system 121 provided in the stage 120.

FIG. 7, part (A) shows an example of a case where the temperature in thewafer 400 on the stage 120 is non-uniform. Specifically, it shows astate in which the wafer 400 has high temperature in the center andlower temperature from the center to the edge.

On the other hand, FIG. 7, part (B) shows an example of temperaturecontrol by the heating and cooling system 121 in a case where the wafer400 is in the state shown in FIG. 7, part (A).

In this case, to uniformize the temperature, for the center of the wafer400, cooling is performed by flowing the refrigerant b1 into the coolingbranch tube 1212 that is disposed in the center, and, for the edge ofthe wafer 400, heating is performed by generating heat for the heaterwire 1215 disposed at the edge. In this process, the flow rate of therefrigerant b1 to the cooling branch tube 1212 is controlled to increaseas it gets closer to the center and decrease as it gets further awayfrom the center. Instead, the calorific value of the heater wire 1215 iscontrolled to become smaller as it gets closer to the center and largeras it gets further away from the center.

In this manner, in the storage device 1 of the present embodiment, inwhich the heating and cooling system 121 is provided in the stage 120,the temperature in the wafer 400 on the stage 120 can be controlled tobe uniform. Note that, in FIG. 7, for the sake of clarity, a state inwhich the temperature in the center of the wafer 400 rises, and thetemperature in the wafer 400 becomes non-uniform is shown. However, thenon-uniformity of the temperature in the wafer 400 may appear in variousstates depending on an access status to the NAND chip 420, etc. In thestorage device 1 of the present embodiment, which sets a plurality oftemperature control areas a1 on the stage 120, no matter in what statethe non-uniformity of temperature appears, the temperature in the wafer400 can be appropriately uniformized.

In addition, although details of the cooling system 310 of the stocker300 will be described later, the wafer 400 stored in the stocker 300 iscooled to low temperature, below room temperature, which is suitable forlong-term storage of data. In contrast, it is preferred that writing ofdata to the NAND chip 420 and reading of data from the NAND chip 420 beperformed at high temperature, above room temperature. In the storagedevice 1 of the present embodiment in which the heating and coolingsystem 121 is provided in the stage 120, when replacing the wafer 400 inthe prober 100, it is possible to raise the temperature of the wafer 400conveyed from the stocker 300 at low temperature to temperature suitablefor writing data to the NAND chip 420 and reading data from the NANDchip 420 before being electrically connected to the probe card 110.Furthermore, upon contact, it is also possible to prevent both the probe115 of the probe card 110 and the pad electrode 410 of the wafer 400from being damaged.

In addition, in the storage device 1 of the present embodiment where thestage 120 is provided with the heating and cooling system 121, whenreplacing the wafer 400 in the prober 100, the wafer 400 on the stage120 maintained above room temperature can be cooled, for example, belowroom temperature on the stage 120 after it is electrically disconnectedfrom the probe card 110, and before it is conveyed to the stocker 300.By storing the wafer 400 that has been cooled on the stage 120, in thestocker 300, it is possible to prevent the temperature in the stocker300 from rising, even if temporarily, and prevent the effect on otherwafers 400 in the stocker 300. Furthermore, a cooling system may also beprovided in the storage conveyance system 200 interposed between theprober 100 and the stocker 300 to cool the wafer 400 that has beenmaintained above room temperature on the stage 120 of the prober 100 tobelow room temperature.

As the temperature control system in the probe card 110, the heating andcooling system 112, the cooling system 113, and the heat insulatingmaterial 114 (see FIG. 1) are provided.

The heating and cooling system 112 is, for example, a temperaturecontrol system using electric heating and cooling tubes similar to theheating and cooling system 121 of the stage 120. Since it may be similarto the heating and cooling system 121 of the stage 120, descriptions ofthe configuration thereof will be omitted. It may also be configureddifferently from the heating and cooling system 121 of the stage 120.

The heating and cooling system 112 is provided on, for example, thebottom surface side in the probe card 110, facing the wafer 400 on thestage 120, so that the temperature of the probe card 110 roughly matchesthe temperature of the wafer 400, or more precisely, so that thetemperature of the probe 115 roughly matches the temperature of the padelectrode 410.

This enables the storage device 1 of the present embodiment to stabilizethe electrical connection between the wafer 400 and the probe card 110when the probe 115 contacts the pad electrode 410.

The cooling system 113 of the probe card 110 is, for example, atemperature control system using heat dissipation or cooling tubes. Thecooling system 113 is provided on, for example, the top surface side inthe probe card 110 to operate the device 111 mounted on the printedcircuit board PCB of the probe card 110 at a temperature equal to orlower than a threshold value; in other words, so that the temperature ofthe device 111 does not exceed the threshold value. The control of thecooling system 113 is executed by the controller 111-1, which is one ofthe devices 111. The controller 111-1 controls the cooling system 113based on the temperature of the controller 111-1 measured by itself orthe temperature measured by other devices on the printed circuit boardPCB. The cooling system 113, like the heating and cooling system 112 andthe heating and cooling system 121 of the stage 120, can control thetemperature in each temperature control area set in advance. Thistemperature control area may correspond to the temperature control areaa1 set on the stage 120, or may be set independently.

This allows the storage device 1 of the present embodiment to continueoperating the device 111 mounted on the probe card 110 in appropriateenvironment.

In addition, the probe card 110 is provided with a heat insulatingmaterial with high thermal resistance between, for example, the topsurface where the device 111 is mounted and, for example, the bottomsurface facing the wafer 400. By installing the heat insulating material114, the storage device 1 of the present embodiment thermally insulatesthe inside of the probe card 110 between the top surface side and bottomsurface side, enabling different temperatures to be maintained,respectively. More specifically, for example, the top surface side canbe maintained at temperature suitable for the device 111, and, forexample, the bottom surface side can be maintained at temperature thatroughly matches the temperature of the wafer 400 on the stage 120.

FIG. 8 is a diagram for explaining an example of a mechanism in whichthe device 111 (the controller 111-1) on the probe card 110 centrallycontrols the temperature of the prober 100 in the storage device 1.

The probe card 110 is provided with a ceramic printed circuit board PCB1101 having high heat dissipation effect. Some of the devices 111disposed on, for example, the top surface of this ceramic printedcircuit board PCB 1101 includes a thermometer 1111 that measures thetemperature of the device 111. The controller 111-1 also includes thethermometer 1111. The controller 111-1 first executes temperaturecontrol using the cooling system 113 so that the temperature of thedevice 111 is maintained at or below a threshold value based on thetemperature measured by these thermometers 1111, including its ownthermometer 1111. As described above, the controller 111-1 can executetemperature control using the cooling system 113 in each temperaturecontrol area that is set in advance. The thermometer 1111 that measuresthe temperature of the device 111 may be outside the device 111.

For example, on the bottom surface of the ceramic printed circuit boardPCB 1101, a probe unit 1103 is disposed via an interposer 1102. Theprobe 115 is provided at a distal end portion of the probe unit 1103.Furthermore, on the bottom surface side of the ceramic printed circuitboard PCB 1101, for example, a thermometer 1104 that can outputtemperature data to the controller 111-1 is provided.

In addition, as mentioned above, a thermometer (430, 1201) is providedin at least one of the wafer 400 and the stage 120. The controller 111-1secondly executes temperature control using the heating and coolingsystem 112 of the probe card 11 and the heating and cooling system 121of the stage 120 so that the temperature of the probe 115 and thetemperature of the pad electrode 410 roughly match based on thetemperature measured by the thermometer 1104 provided in the probe card110 and the temperature measured by the thermometer 430 provided in thewafer 400 or the temperature measured by the thermometer 1201 providedin the stage 120. At the same time, the controller 111-1 executestemperature control using the heating and cooling system 121 of thestage 120 so that the temperature in the wafer 400 becomes uniform.

In other words, in the storage device 1 of the present embodiment, thedevice 111 disposed on the probe card 110 is capable of monitoring thetemperature of multiple locations of the probe card 110, the stage 120,and the wafer 400 on the stage 120.

Note that, in FIG. 8, a formation on the wafer 400 indicated by symbolc1 is an alignment mark used for aligning the probe 115 of the probecard 110 with respect to the pad electrode 410. Furthermore, in FIG. 8,the X direction is a direction of word lines and the Y direction is adirection of the bit lines. The movement of the stage 120 holding thewafer 400 in the horizontal direction by the drive unit 130 is performedwith reference to this alignment mark c1. The probe card 110 may beprovided with a camera for detecting a representative position (here,the alignment mark c1) on the wafer 400. The drive control unit 13 canrecognize a reference position more accurately based on the informationfrom the camera, and can perform precise alignment.

FIG. 9 shows a plurality of probes 115 disposed on a first surface 110Aof the probe card 110.

In FIG. 9, a case is exemplified in which the same number of probes 115as the number of pad electrodes 410 of all NAND chips 420 of the wafer400 are disposed on the first surface 110A of the probe card 110.

In this case, the probes 115 of the probe card 110 are in contact withall pad electrodes 410 of all NAND chips 410 in the wafer 400 all atonce, and all the NAND chips can be controlled by the controller 111-1.

FIG. 10 shows a plurality of controllers 111-1 disposed on a secondsurface 110B of the probe card 110.

In FIG. 10, a case in which 16 controllers 111-1 (controllers 111-1-1,111-1-2, . . . , 111-1-16) are disposed is exemplified. In a case wherea single wafer includes 1024 NAND chips 420, and 16 controllers 111-1are disposed on the second surface 110B of the probe card 110, eachcontroller 111-1 should control 64 NAND chips 420 via the probe 115.

FIG. 11 is a diagram for explaining an example of an operation of thedevice 111 implemented on a prober 100.

Here, it is assumed that a plurality of controllers 111-1 share controlof a plurality of NAND chips 420 formed on the wafer 400. In otherwords, it is assumed that multiple controllers 111-1 are disposed on theprobe card 110.

A connector 111-3 into which a riser cable 111A for connecting the probecard 110 to an external device, such as the host 2 (see FIG. 3), isinserted is disposed on the probe card 110. An interface switch (forexample, a PCIe (registered trademark) switch) 111-4 for exclusively andselectively connecting to the connector 111-3 and one controller 111-1among multiple controllers 111-1 is disposed on the probe card 110. Bythe interface switch 111-4 switching appropriately, for example, whendata read is requested from the host 2, the data read request istransmitted to the controller 111-1 that controls the corresponding NANDchip 420. The controller 111-1 that receives this request reads the datafrom the NAND chip 420, and transmits the read data to the host 2. Thedata transmitted from the controller 111-1 is relayed to the connector111-3 by the interface switch 111-4, and is transferred to the host 2via the riser cable 111A.

In the storage device 1 of the present embodiment, the temperature ofthese multiple devices 111 that are disposed on the probe card 110 ismaintained at or below a threshold value by the cooling system 113 ofthe probe card 110. Furthermore, in addition to the controller 111-1 andthe interface switch 111-4, various LSI chips and semiconductorcomponents such as FPGAs, relays, capacitors, etc., may be implementedon the prober 100.

Next, the cooling system 310 provided in the stocker 300 will bedescribed.

FIG. 12 shows a first example of the cooling system 310.

The stocker 300 is provided with the same number of shutters 301 thatopen and close when the wafers 400 are taken in and out, as the numberof wafers 400 that can be stored therein. When taking out the wafers 400from the stocker 300 or storing the wafers 400 in the stocker 300, toprevent cool air in the stocker 300 from escaping, any shutter 301 amongthe plurality of shutters 301 is selectively opened and closed. Notethat the stocker 300 may also be configured to have one shutter 301 andmove the entire stock of the storages (wafers 400) stored therein up anddown.

In the first example, the stocker 300 is provided with an intake port311 for feeding cooling air d1, and an exhaust port 312 for dischargingcooling air d2 that has flowed through the stocker 300. The cooling aird1 is, for example, cooled air under high pressure. The cooling system310 of the stocker 300 in the present example closes the entrance andexit of the wafer 400 with the shutter 301, continues to feed thecooling air d1 from the intake port 311, and continues to fill thestocker 300 with the cooling air d1 that is kept below room temperature,to thereby cool the entire stocker 300. In other words, the wafer 400 inthe stocker 300 is cooled so that the temperature becomes suitable forlong-term storage of data.

FIG. 13 shows a second example of the cooling system 310.

In the second example, a cooling tube 313 for distributing refrigerante1 is provided, for example, on the side peripheral wall of the stocker300 so as to cover the entire side surface of the stocker 300. Therefrigerant e1 is water or liquid nitrogen cooled by electronic cooling.The cooling system 310 of the stocker 300 in the present example closesthe entrance and exit of the wafers 400 by the shutters 301, distributesthe refrigerant e1 to the cooling tube 313 provided on the peripheralwall of the stocker 300, and cools the air inside the stocker 300, tothereby cool the entire stocker 300. In other words, the wafer 400 inthe stocker 300 is cooled to temperature suitable for long-term storageof data. Note that the cooling tube 313 may be provided inside thestocker 300.

In addition to using the cooling air d1 and the refrigerant e1, forexample, an electronic cooling system using Peltier elements may beprovided on a portion supporting the wafer 400 in the stocker 300, aportion connected to this support portion, or the entire stocker 300, tothereby cool the wafer 400 in the stocker 300.

In this manner, in the storage device 1 of the present embodiment inwhich the stocker 300 is provided with the cooling system 310, it ispossible to store the wafers 400 in the stocker 300 while maintaininglow temperature below room temperature, which is suitable for long-termstorage of data.

Next, the air conditioning control system 500 (see FIG. 1) will bedescribed.

As described above, the wafers 400 in the stocker 300 are cooled to lowtemperature below room temperature. Therefore, in the case of taking outa wafer 400 from the stocker 300 and conveying the wafer 400 to theprober 100 to replace a wafer 400 in the prober 100 with the wafer 400in the stocker 300, there is a possibility that the water vapor in theair in the storage conveyance system 200 may condense (i.e.,condensation may occur) on the low-temperature wafer 400 and on thestorage conveyer 210 that conveys the wafer 400. To prevent thiscondensation, the storage device 1 of the present embodiment is providedwith the air conditioning control system 500 to replace the atmospherein the storage conveyance system 200 with dry air, noble gas, inert gas,or the like that does not contain water.

The air conditioning control system 500 not only replaces the atmospherein the storage conveyance system 200 but also in the prober 100 and thestocker 300 with dry air, noble gas, inert gas, or the like that doesnot contain water. As a result, in the storage device 1 of the presentembodiment, condensation can be prevented almost completely on the wafer400. Note that, since it is preferable that there is no oxygen inaddition to water in the space where the wafer 400 is handled, it ispreferable to replace the atmosphere in the prober 100, the storageconveyance system 200, and the stocker 300 with noble gas or inert gas.

Furthermore, since it is preferable to cool not only the inside of thestocker 300 but also the inside of the storage conveyance system 200that conveys, to the stocker 300, the wafers 400 that have beenmaintained at high temperature above room temperature in the prober 100,the cooling system may also be provided in the storage conveyance system200 as described above.

Furthermore, the stocker 300 is cooled to maintain the charge retentionproperties of the NAND chips 420 of the wafers 400 for a long time. Thetemperature of the wafer 400 may be at room temperature; however, sincethe cooler the temperature, the higher the charge retention property is,a temperature of 0° C. or lower may also be used. However, at the lowtemperature equal to or lower than 0° C., there may be electrical sideeffects due to condensation of water in the atmosphere, such as a shortcircuit between wires. From this point of view, it is preferable toreplace the atmosphere in the stocker 300 with dry air, noble gas suchas argon, or inert gas such as nitrogen that does not contain water.

In this manner, in the storage device 1 of the present embodiment thatis provided with the air conditioning control system 500, which is akind of temperature control system, condensation can be prevented on thewafer 400 and on the storage conveyer 210.

FIG. 14 is a flowchart showing an example of a flow of the temperaturecontrol at the time of replacement of the wafer 400 executed in thestorage device 1 of the present embodiment.

The storage device 1 electrically disconnects the wafer 400 from theprobe card 110 using the drive unit 130 (S1). The storage device 1 coolsthe wafer 400 electrically disconnected from the probe card 110 on thestage 120 (S2). In this process, the controller 111-1 acquires thetemperature from the thermometer (430, 1201) through, for example, theI²C bus. The storage device 1 conveys the wafer 400 cooled, for example,below room temperature from the prober 100 to the stocker 300 by thestorage conveyance system 200 (S3).

Subsequently, the storage device 1 conveys the wafer 400 to beaccommodated in the prober 100 in replacement with the wafer 400 takenout from the prober 100, from the stocker 300 to the prober 100 usingthe storage conveyance system 200 (S4). The storage device 1 raises thetemperature of the wafer 400 to be electrically connected to the probecard 110 on the stage (S5). Again, in this process, the controller 111-1acquires the temperature from the thermometer (430, 1201) through, forexample, the I²C bus. The storage device 1 electrically connects thewafer 400, which has been raised to, for example, temperature above roomtemperature that is suitable for writing and reading data to the NANDchip 420, with the probe card 110 using the drive circuit (S6).

As described above, the storage device 1 of the present embodiment, inwhich the temperature control system is provided in each of the prober100, the storage conveyance system 200, and the stocker 300, canappropriately perform various temperature controls for the wafer 400.

In addition, the heating and cooling system 121 provided in the stage120 of the prober 100 can be used to refresh the wafer 400. The refreshis a process for leveling variations in properties between memory cellsin a NAND chip for writing or reading of data, which have been degradedby read/write stress. This process also recovers the data retentionfunction of the NAND chip. For example, to recover degradation byannealing at approximately 300° C., the temperature of the wafer 400 israised on the stage 120 and the refresh is performed. For this purpose,an intake port provided in the prober 100 and a supply system providedin the prober 100 for nitrogen, argon, helium, krypton, xenon, and thelike are used to seal the inside of the prober 100 with these inertgases. In other words, the concentration of water and oxygen included inthe atmosphere is reduced. Note that a different atmosphere may be usedto seal each area in the prober 100. In this manner, by replacing theatmosphere with inert gas, and using the heating and cooling system 121provided in the stage 120, the electrodes of the wafer 400 can beprevented from oxidation. In other words, in the storage device 1 of thepresent embodiment, a refresh system that raises the temperature of thewafer 400 on the stage 120 and seals the area around the wafer 400 withan inert gas may be provided in the prober 100.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the inventions. Indeed, the novel embodiments described hereinmay be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the embodimentsdescribed herein may be made without departing from the spirit of theinventions. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the inventions.

What is claimed is:
 1. A storage device comprising: a control apparatusconfigured to write data to or read data from a storage medium thatincludes a plurality of non-volatile memory chips; and a stockerconfigured to store a plurality of the storage media that are detachedfrom the control apparatus, wherein the control apparatus includes afirst temperature control system configured to raise temperature of thestorage medium to a first temperature or higher, and the stockerincludes a second temperature control system configured to cool thestorage medium to a second temperature or lower, the second temperaturebeing lower than the first temperature.
 2. The storage device of claim1, wherein the control apparatus further includes: a stage configured tohold the storage medium; a probe card including a plurality of probes ona first surface, the first surface facing the storage medium when thestorage medium is held by the stage; and a drive unit configured to:move at least one of the stage or the probe card to bring a plurality ofpad electrodes provided on the storage medium into contact with theplurality of probes, the plurality of pad electrodes being provided on asurface of the storage medium that faces the probe card when the storagemedium is held by the stage; or separate the plurality of pad electrodesand the plurality of probes that are in contact with each other, whereinthe drive unit is configured to bring the plurality of pad electrodes ofthe storage medium into contact with the plurality of probes after thefirst temperature control system raises the temperature of the storagemedium to the first temperature or higher on the stage.
 3. The storagedevice of claim 2, wherein the first temperature control system includesa plurality of temperature control systems formed in the stage, each ofthe plurality of temperature control systems being configured to performtemperature control for each of a plurality of areas of the storagemedium held by the stage.
 4. The storage device of claim 3, wherein thefirst temperature control system is configured to maintain temperatureof each of the plurality of areas of the storage medium within a firstrange using the plurality of temperature control systems.
 5. The storagedevice of claim 4, wherein the plurality of areas are areascorresponding to respective positions of the plurality of non-volatilememory chips in the storage medium.
 6. The storage device of claim 2,wherein the first temperature control system includes a temperaturecontrol system configured to control temperature of the first surface ofthe probe card.
 7. The storage device of claim 2, wherein the probe cardfurther includes a plurality of semiconductor components on a secondsurface opposing to the first surface, and the first temperature controlsystem includes a temperature control system configured to cool theplurality of semiconductor components on the second surface.
 8. Thestorage device of claim 7 wherein the probe card further includes heatinsulating material between the first surface and the second surface. 9.The storage device of claim 7, wherein the plurality of semiconductorcomponents include at least one of (A) at least one controllerconfigured to control the non-volatile memory chips, (B) an interfaceswitch configured to selectively operate a plurality of the controllers,(C) a relay, and (D) a capacitor.
 10. The storage device of claim 7,wherein at least one of the plurality of semiconductor components isconfigured to monitor at least one of temperature measured by athermometer provided in the stage and temperature measured by athermometer provided in the probe card.
 11. The storage device of claim1, wherein the second temperature control system includes a coolingsystem configured to use cooling water, cooling air or liquid nitrogenas refrigerant.
 12. The storage device of claim 1, wherein the secondtemperature control system includes an electronic cooling systemconfigured to use a Peltier element provided in a first portionconfigured to hold the storage medium, or in a second portion connectedto the first portion.
 13. The storage device of claim 2, wherein thecontrol apparatus further includes a refresh system configured to sealaround the storage medium with a noble gas or an inert gas, and to raisethe temperature of the storage medium on the stage using the firsttemperature control system.
 14. The storage device of claim 13, whereinthe noble gas or the inert gas is one of nitrogen, argon, helium,krypton, or xenon.
 15. The storage device of claim 2, wherein thecontrol apparatus is further configured to, when replacing the storagemedium in contact with the plurality of probes from a first storagemedium to a second storage medium stored in the stocker, cool the firststorage medium maintained to the first temperature or higher, to lowerthan the first temperature on the stage using the first temperaturecontrol system.
 16. The storage device of claim 2, wherein the controlapparatus is further configured to, when replacing the storage medium incontact with the plurality of probes from a third storage medium to afourth storage medium stored in the stocker, raise temperature of thefourth storage medium cooled to the second temperature or lower, to thefirst temperature or higher on the stage using the first temperaturecontrol system, and bring the plurality of pad electrodes of the fourthstorage medium into contact with the plurality of probes using the driveunit.
 17. The storage device of claim 1, further comprising a conveyancesystem configured to convey the storage medium from the controlapparatus to the stocker or convey the storage medium from the stockerto the control apparatus, wherein the first temperature is roomtemperature, and the conveyance system includes a third temperaturecontrol system configured to adjust air in the conveyance system for apurpose of preventing condensation during conveyance of the storagemedium cooled to the second temperature or lower from the stocker to thecontrol apparatus.
 18. The storage device of claim 1, wherein thestorage medium is a semiconductor wafer.
 19. A control method of astorage device, the storage device including a control apparatus and astocker, said method comprising: raising temperature of a storage mediumthat includes a plurality of non-volatile memory chips to a firsttemperature or higher, in the control apparatus that is configured towrite data to or read data from the storage medium loaded on a stage;cooling a plurality of the storage media to a second temperature orlower, while the stocker stores the plurality of the storage mediadetached from the control apparatus, the second temperature being lowerthan the first temperature; and when replacing the storage mediumconnected to a probe card of the control apparatus from a first storagemedium to a second storage medium stored in the stocker, cooling thefirst storage medium maintained to the first temperature or higher, tolower than the first temperature in the control apparatus; raisingtemperature of the second storage medium cooled to the secondtemperature or lower, to the first temperature or higher in the controlapparatus; and loading the second storage medium on the stage.
 20. Thecontrol method of claim 19, wherein the storage medium is asemiconductor wafer.